The present invention relates to a system for performing work within a sealed enclosure such as a hot cell. More particularly, the present invention relates to a system that allows an operator located outside of the sealed enclosure to control a remote arm located in the sealed enclosure.
Sealed enclosures, commonly known as "hot cells", are used throughout the nuclear industry to contain radiation around radioactive handling equipment. A typical hot cell includes a ceiling, a floor and walls formed of concrete having a thickness sufficient to prevent radiation and radioactive particles from leaving the hot cell. Holes of limited diameter (for example 10 inches) are provided at various locations in the walls. Each hole allows a manipulator to be inserted into the hot cell to perform work on the equipment. The manipulator includes a movable arm portion that can be inserted through the hole and a straight portion that is supported by the inner wall of the hole. Controls are provided on an end of the straight portion and are connected directly to the movable arm with cables to allow an operator to control movement of the arm. When the operator's work is completed, the operator removes the manipulator from the hot cell by pulling it out back through the hole. Since the manipulator, and in particular the movable arm, must be inserted through the hole, the movable arm can not be any larger than the diameter of the hole. This is a significant disadvantage because it limits the carrying capacity of the manipulator.